Thermo Scientific HM525 NX Operator Guide
48
Display Lock
Note
The display lock is used to avoid unwanted changes to the settings of the HM525 NX.
To activate the Display Lock:
•
Press the "Menu" button on the Main
screen.
•
The Menu screen will be displayed.
•
Press “Display Lock” to activate the
display lock immediately.
Deactivate the Display Lock
•
Press the "Lock" Symbol three times.
Note
The symbol changes its colour (red - yellow - green)
each time it is pressed.
Defrost
Inevitably, when working on the microtome, the dry cold air of the cryo chamber mixes with the warm
humid air outside the chamber. Frost forms on the finned evaporator. The increasing thickness of the
frost reduces the efficiency of the evaporator. For this reason, the daily defrosting is necessary.
Remove the specimens from the cryo chamber during defrosting, as the temperature inside the
chamber will increase. Do not leave or store specimens inside the HM525 NX over a long
period of time. Due to a power failure or other unexpected malfunctions of the instrument,
specimens might be damaged.
Note
Set the time of the daily defrosting on the control panel. The period of the defrosting takes approximately 1
hour and varies according to the thickness of the frost.
Possible frost build-up on the microtome or on the knife carrier is not removed by defrosting the
instrument. However, the frost recedes after defrosting as now the evaporator is fully efficient again.
In addition, the instrument is equipped with an immediate defrosting function. The immediate defrosting
takes maximum 60 minutes.